Motor vehicles powered by internal combustion engines are commonly used to transport and deliver goods in many places in the world. In a number of these locales, environmental and other concerns have increased the use of motor fuels considered to be alternative fuels, as compared with the more expected gasoline and diesel fuels often used. One of the more popular alternative fuels is liquefied petroleum gas or LPG. LPG is a catchall term used to describe a variety of fuels such as commercial propane, butane which have similar physical qualities of being liquid when confined at near room temperature when moderately compressed. When in liquid form, these fuels are up to two hundred and fifty times more dense as compared to their gaseous form. Thus, it is preferable for fuel systems of LPG powered vehicles store the fuel in a liquid form until the fuel is supplied by an injector into a combustion chamber of an engine, at which point the fuel may be vaporized to improve combustion. Further, when using LPG in an engine with fuel injection, provision should be made for excess fuel from the injector rail to be returned to the fuel tank.
While many LPG fueled vehicles are factory conversions or retrofits of vehicles designed to use more traditional fuels, such as gasoline or diesel, the location of the tanks, pumps and other equipment used for the more traditional fuels are not the most well suited for LPG fuel systems. Maintenance and repair considerations vary between the more traditional fuel systems and LPG systems.
Improvements to the known systems for storing liquid LPG and supplying gaseous LPG to the engine are desirable.